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<div class='is-node' id='write'><p><a
        href='https://xiaozhuanlan.com/kunminx'><span>《重学安卓》</span></a><span>付费读者加微信进群：myatejx</span>
</p>
    <p>&nbsp;</p>
    <h2><a class="md-header-anchor" name="前言"></a><span>前言</span></h2>
    <p><span>很高兴见到你！</span></p>
    <p><span>上周我在 各大技术社区 发表了一篇 </span><a
            href='https://juejin.im/post/5dafc49b6fb9a04e17209922'><span>《Jetpack MVVM 精讲》</span></a><span>，原以为在 知识网红 唱衰安卓 的 2019 会无人问津，没想到文章一经发布，从 国内知名公司 的架构师、技术经理，到 世界级公司 的 Android 开发 都在看。😉</span>
    </p>
    <p><img alt='reader_say.png'
            referrerPolicy='no-referrer'
            src='https://upload-images.jianshu.io/upload_images/57036-5445e7b4d66d97c7.png'/></p>
    <p><span>并且从读者的反馈来看，近期大部分安卓开发 已跳出舒适圈，开始尝试认识和应用 Jetpack MVVM 到实际的项目开发中。</span></p>
    <p><span>只可惜，关于 Jetpack MVVM，网上多是 </span><strong><span>东拼西凑、人云亦云、通篇贴代码</span></strong><span> 的文章，这不仅不能提供完整的视角 来帮助读者 首先明确背景状况，更是给还没入门 Jetpack 的读者 </span><strong><span>徒添困扰</span></strong><span>、起到 </span><strong><span>劝退</span></strong><span> 的作用。</span>
    </p>
    <p>
        <span>好消息是，这一期，我们带着 </span><strong><span>精心打磨的 Jetpack MVVM 最佳实践案例</span></strong><span> 来了！</span>
        &nbsp;</p>
    <figure>
        <table>
            <thead>
            <tr>
                <th style='text-align:center;'><span>是让人 爱不释手 的 交互设计！</span></th>
                <th style='text-align:center;'><span>是 连贯 的 用户体验</span></th>
                <th style='text-align:center;'><span>唯一可信源 的 统一分发</span></th>
            </tr>
            </thead>
            <tbody>
            <tr>
                <td style='text-align:center;'><img
                        alt='1231111323.gif'
                        referrerPolicy='no-referrer'
                        src='https://upload-images.jianshu.io/upload_images/57036-0a5cdc68f003211a.gif'/>
                </td>
                <td style='text-align:center;'><img
                        alt='222.gif'
                        referrerPolicy='no-referrer'
                        src='https://upload-images.jianshu.io/upload_images/57036-2b21db531e51ff03.gif'/>
                </td>
                <td style='text-align:center;'><img
                        alt='333.gif'
                        referrerPolicy='no-referrer'
                        src='https://upload-images.jianshu.io/upload_images/57036-9a541148ce5bed2e.gif'/>
                </td>
            </tr>
            </tbody>
        </table>
    </figure>
    <p>&nbsp;</p>
    <figure>
        <table>
            <thead>
            <tr>
                <th style='text-align:center;'><span>横竖屏布局 的 无缝切换</span></th>
            </tr>
            </thead>
            <tbody>
            <tr>
                <td style='text-align:center;'><img
                        alt='444.gif'
                        referrerPolicy='no-referrer'
                        src='https://upload-images.jianshu.io/upload_images/57036-688f3eafc76cfa27.gif'/>
                </td>
            </tr>
            </tbody>
        </table>
    </figure>
    <p>&nbsp;</p>
    <h2><a class="md-header-anchor" name="项目简介"></a><span>项目简介</span></h2>
    <p><span>本人拥有 3 年的 移动端架构 践行和设计经验，领导团队重构的 中大型项目 多达十数个，对 Jetpack MVVM 架构在 确立规范化、标准化 开发模式 以 </span><strong><span>减少不可预期的错误</span></strong><span> 所作的努力，有着深入的理解。</span>
    </p>
    <p><span>在这个案例中，我将为你展示，Jetpack MVVM 是如何 </span><strong><span>蕴繁于简</span></strong><span> 地 将原本十分容易出错、一出错就会耽搁半天时间的开发工作，通过 寥寥的几行代码 轻而易举地完成。😉</span>
    </p>
    <blockquote><p><span>👆👆👆 划重点！</span></p></blockquote>
    <p>&nbsp;</p>
    <p><span>在这个项目中，</span></p>
    <blockquote><p>
        <span>我们为 </span><strong><span>横、竖屏</span></strong><span> 的情况 分别安排了两套 </span><strong><span>截然不同的布局</span></strong><span>，并且在 </span><a
            href='https://xiaozhuanlan.com/topic/0213584967'><span>生命周期</span></a><span>、</span><a
            href='https://xiaozhuanlan.com/topic/7692814530'><span>重建机制</span></a><span>、</span><a
            href='https://xiaozhuanlan.com/topic/7692814530'><span>状态管理</span></a><span>、</span><a
            href='https://xiaozhuanlan.com/topic/9816742350'><span>DataBinding</span></a><span>、</span><a
            href='https://xiaozhuanlan.com/topic/6257931840'><span>ViewModel</span></a><span>、</span><a
            href='https://xiaozhuanlan.com/topic/0168753249'><span>LiveData</span></a><span> 、</span><a
            href='https://xiaozhuanlan.com/topic/5860149732'><span>Navigation</span></a><span> 等知识点的帮助下，通过寥寥几行代码，轻松做到 </span><strong><span>在横竖屏两种布局间 无缝地切换，并且不产生任何 预期外的错误</span></strong><span>。</span>
    </p></blockquote>
    <p>&nbsp;</p>
    <blockquote><p><span>我们在多个 Fragment 页面 分别安排了 </span><strong><span>播放状态 指示器</span></strong><span>（包括 播放暂停按钮状态、播放列表当前索引指示 等），并向你展示了 如何 以及为何 通过 </span><a
            href='https://xiaozhuanlan.com/topic/0168753249'><span>LiveData</span></a><span> </span><strong><span>配合</span></strong><span> 作为唯一可信源 的 </span><a
            href='https://xiaozhuanlan.com/topic/6257931840'><span>ViewModel</span></a><span> 或单例，来实现 </span><strong><span>全应用范围内 可追溯事件 的统一分发</span></strong><span>。</span>
    </p></blockquote>
    <p>&nbsp;</p>
    <blockquote><p><span>我们在 Fragment 和 Activity 之间分别安排了 跨页面通信，从而向你展示 如何基于 </span><strong><span>迪米特原则</span></strong><span>（也称 最少知道原则）、通过 UnPeekLiveData 和 应用级 SharedViewModel 来实现 </span><strong><span>生命周期安全的、确保消息同步一致性和可靠性的 页面通信</span></strong><span>（事件回调）。</span>
    </p></blockquote>
    <p>&nbsp;</p>
    <blockquote><p>
        <span>我们在 </span><code>ui.page</code><span> 、</span><code>data.repository</code><span>、</span><code>bridge.request</code><span> 等目录下，分别安排了 视图控制器、</span><a
            href='https://xiaozhuanlan.com/topic/6257931840'><span>ViewModel</span></a><span> 、DataRepository 等 内容，从而向你展示，</span><strong><span>单向依赖</span></strong><span> 的架构设计，是如何通过分层的 数据请求和响应，来 </span><strong><span>规避 内存泄漏</span></strong><span> 等问题。</span>
    </p></blockquote>
    <p>&nbsp;</p>
    <blockquote><p>
        <span>本项目的代码一律采用 经过 ISO 认证的 标准化工业级语言 Java 来编写。并且，在上述目录 所包含的 类中，我们大都 </span><strong><span>提供了丰富的注释</span></strong><span>，来帮助你理解 骨架代码 为何要如此设计、如此设计能够 </span><strong><span>在软件工程的背景下</span></strong><span> 避免哪些不可预期的错误。</span>
    </p></blockquote>
    <p>&nbsp;
        &nbsp;</p>
    <p><span>除了 </span><strong><span>在 蕴繁于简 的代码中 掌握 MVVM 最佳实践</span></strong><span>，你还可以 从这个开源项目中 获得的内容 包括：</span>
    </p>
    <ol start=''>
        <li><span>整洁的代码风格 和 标准的资源命名规范。</span></li>
        <li><span>对 视图控制器 知识点的 深入理解 和 正确使用。</span></li>
        <li><span>AndroidX 和 Material Design 2 的全面使用。</span></li>
        <li><span>ConstraintLayout 约束布局的最佳实践。</span></li>
        <li><strong><span>优秀的 用户体验 和 交互设计</span></strong><span>。</span></li>
        <li><span>绝不使用 Dagger，绝不使用奇技淫巧、编写艰深晦涩的代码。</span></li>
        <li><span>The one more thing is：</span></li>
    </ol>
    <p><span>即日起，可在 应用商店 下载体验！</span></p>
    <p>&nbsp;</p>
    <p><a href='https://www.coolapk.com/apk/247826'><img
            alt='google-play1.png'
            referrerPolicy='no-referrer'
            src='https://upload-images.jianshu.io/upload_images/57036-f9dbd7810d38ae95.png'/></a><span> </span><a
            href='https://www.coolapk.com/apk/247826'><img
            alt='coolapk1.png'
            referrerPolicy='no-referrer'
            src='https://upload-images.jianshu.io/upload_images/57036-6cf24d0c9efe8362.png'/></a>
    </p>
    <p>&nbsp;
        &nbsp;</p>
    <h2><a class="md-header-anchor" name="thanks-to"></a><span>Thanks to</span></h2>
    <p><a href='https://developer.android.google.cn/jetpack/androidx'><span>AndroidX</span></a></p>
    <p><a href='https://developer.android.google.cn/jetpack/'><span>Jetpack MVVM</span></a></p>
    <p><a href='https://github.com/material-components/material-components-android'><span>material-components-android</span></a>
    </p>
    <p><a href='https://play.google.com/store/apps/details?id=com.tencent.qqmusiclocalplayer'><span>轻听</span></a>
    </p>
    <p>
        <a href='https://github.com/umano/AndroidSlidingUpPanel'><span>AndroidSlidingUpPanel</span></a>
    </p>
    <p><span>项目中使用的 图片素材 来自 </span><a href='https://unsplash.com/'><span>UnSplash</span></a><span> 提供的 </span><strong><span>无版权免费图片</span></strong><span>。</span>
    </p>
    <p><span>项目中使用的 音频素材 来自 </span><a
            href='https://www.bensound.com/'><span>BenSound</span></a><span> 提供的 </span><strong><span>无版权免费音乐</span></strong><span>。</span>
    </p>
    <p>&nbsp;
        &nbsp;</p>
    <h2><a class="md-header-anchor" name="my-pages"></a><span>My Pages</span></h2>
    <p><span>Email：</span><a href='mailto:kunminx@gmail.com'><span>kunminx@gmail.com</span></a></p>
    <p><span>Home：</span><a href='https://www.kunminx.com/'><span>KunMinX 的个人博客</span></a></p>
    <p><span>Juejin：</span><a href='https://juejin.im/userBean/58ab0de9ac502e006975d757/posts'><span>KunMinX 在掘金</span></a>
    </p>
    <p><a href='https://xiaozhuanlan.com/kunminx?rel=kunminx'><span>《重学安卓》 专栏</span></a></p>
    <p><span>付费读者加微信进群：myatejx</span></p>
    <p><a href='https://xiaozhuanlan.com/kunminx?rel=kunminx'><img
            alt='重学安卓小专栏' referrerPolicy='no-referrer'
            src='https://i.loli.net/2019/06/17/5d067596c2dbf49609.png'/></a></p>
    <h2><a class="md-header-anchor" name="license"></a><span>License</span></h2>
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